Woody encroachment is becoming common in tropical savannas. We studied natural seed rain and performed seed addition experiments in a Brazilian savanna that had not been burned for several decades. We found greater abundance of fire‐sensitive species in the seed rain, likely contributing to woody encroachment. Flexible fire management policies that allow for natural and prescribed fires may be required to maintain savanna diversity.

Th e Brazilian Atlantic Forest is a global biodiversity hotspot, but most of what remains are small fragments. Small fragments are often harsh environments for forest plant recruitment due to edge eff ects and the loss of frugivorous animals that provide seed dispersal. We recorded the one-year reproductive phenology of the keystone palm Syagrus romanzoffi ana in small (<2.5ha) Atlantic Forest fragments in southeastern Brazil. We tested the Janzen-Connell hypothesis with seed-removal experiments and followed the fi ve-year survival of recruits in relation to the distance from parental plants. Palms produced many fruits throughout the year (mean 2,600/plant). More seedlings were found away from parental plants than near them, thereby supporting the Janzen-Connell hypothesis. Almost 45% of seedlings alive in 2010 were dead fi ve years later, but recruitment of new seedlings compensated for this mortality. Distance-dependent factors infl uenced the density of early ontogenetic stages, but had limited eff ects on juveniles or on seed removal. High seed production, seed dispersal provided by disturbance-tolerant frugivores and the relatively long-term survival of adults, seedlings and juveniles seem to allow the persistence of S. romanzoffi ana in the forest fragments, but possibly at the cost of an increased clumped distribution and reduced gene fl ow at the landscape scale.

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